How to Use Function Blocks for Specific Operations
Section
1-4
50
To perform this specific operation
Perform the following
See page:
Sample PI control
Use the ON/OFF Timer block (Block
Model 206).
5-2 Examples of Applied
Control Types (page
161) and Function Block
Reference Manual
PID control with differential gap
Use the Constant Item Setting block
(Block Model 171).
Selective control
Use the Rank Selector block (Block
Model 161).
Analog
control
Using fuzzy control based on
knowledge from ambiguous
expressions
Use the Fuzzy Logic block (Block Model
016).
Performing calculation is engineering
units rather than percentages
Performing special calculations, such
as trigonometric or logrithmic
operation
Use the Arithmetic Operation block
(Block Model 126).
Special math
operations
Calculating statistics (e,g., average,
standard deviation, etc) for time
sequence data
Use the Time Sequence Data Statistics
block (Block Model 153).
Function Block
Reference Manual
Accumulation (accumulator) of
instantaneous analog signals such as
flowrate signals on the Loop Control
Unit
Use the Accumulator for instantaneous
value input block (Block Model 150).
5-1 Basic Examples of
PID Control (page 152)
and Function Block
Reference Manual
Continuous accumulation of 4-digit
accumulated value signals (repeat
signals 0000 to 9999) and conversion
to 8-digit signals
Use the Accumulator for accumulated
value input block (Block Model 184).
Input and accumulation of low-speed
pulse signals such as the power
signal
Use the Contact input/Accumulated
value output block (Block Model 185).
Function Block
Reference Manual
Notification of accumulated values on
a field mechanical counter for contact
inputs
Use the Accumulated Value
Input/Contact Output block (Block Model
186).
Batch flowrate capture
Use the Batch Flowrate Capture block
(Block Model 014).
Ratio control of accumulated values
Use the Batch Flowrate Capture block
(Block Model 014) and the Blended PID
block (Block Model 013).
Addition of accumulated values
Use the Accumulated Value Input Adder
block (Block Model 182)
Accumulation
processing
Multiplication of analog signals with
accumulated values
Use the Accumulated Value Analog
Multiplier block (Block Model 183)
Function Block
Reference Manual
AND, OR and other logical operations
on the Loop Control Unit
One-shot contact output of the ON
input state when the contact state
changes from OFF to ON and vice
versa only in 1-operation cycles
(system common operation cycle)
Constantly ON contacts and other
system contacts
Step progression control and other
control on the Loop Control Unit
Acceptance of relays in the Step
Ladder Program
Use the Step Ladder Program block
(Block Model 301).
Use the Internal Switch block (Block
Model 209).
Execution of special processing at
each fixed cycle longer than operation
cycle in Step Ladder Program
Generate a fixed cycle timing signal by
the Clock Pulse block (Block Model
207).
Appendix-1 How to Use
the Step Ladder Program
Block and Function Block
Reference Manual
Execution of timers/counters on the
Loop Control Unit
Use the Timer block (Block Model 205)
and the Counter block (Block Model
208).
Function Block
Reference Manual
Sequence
control
Changing PID constants and other
parameters in stages according to a
process value (e.g., temperature).
Use the Level Check block (Block Model
210) and the Constant ITEM Setting
block (Block Model 171) together to
change paramters for other blocks
according to the level.
